Nutrients like calcium, iron, and zinc are just as essential as vitamins. The table below shows, in capsule form, how much you need, what foods supply significant amounts, and the functions various minerals perform. Use it to plan a mineral-rich menu. (As with vitamins, however, sometimes diet alone can’t satisfy the need for certain minerals. Pregnancy, menstruation, illness, crash dieting, food allergies, use of medication, or other circumstances may call for mineral supplements.)
Calcium
Primary Functions
Needed for building strong bones and teeth and maintaining strong bones throughout life. Required for normal muscle contraction and relaxation, heart action, nerve function and blood clotting.
Food Sources
Milk and dairy products, sardines, salmon eaten with bones, oysters, tofu, green leafy vegetables, clams, citrus fruit.
Dietary Reference Intake (DRI)*
1,000 milligrams
Deficiency Symptoms
Stunted growth in children, weakened bones in adults, bones that break easily. (Deficiency disease: osteoporosis.)
Chromium
Primary Functions
Works with insulin to take sugar into cells. Involved in breakdown of sugar to release energy.
Food Sources
Brewers yeast, meat, clams, whole grains, unrefined foods, cheeses, nuts.
Dietary Reference Intake (DRI)*
35 micrograms
Deficiency Symptoms
Impaired glucose metabolism. (May lead to adult onset diabetes.)
Copper
Primary Functions
Needed for hemoglobin and to make red blood cells. Forms protective coverings for nerves. Part of several enzymes. May be involved with vitamin C in forming collagen. Needed in respiration and release of energy.
Food Sources
Organ meats, shellfish (especially oysters), whole grains, nuts, legumes, lean meat, fish, fruits, vegetables.
Dietary Reference Intake (DRI)*
900 micrograms
Deficiency Symptoms
Anemia, bone defects, retarded growth, impaired metabolism.
Iodine
Primary Functions
Part of thyroxide, a hormone secreted by the thyroid gland, which helps to regulate growth, development, reproduction, and metabolic rate (rate at which calories are burned.)
Food Sources
Iodized salt, sea salt, seafood, seaweed, foods grown in iodine-rich soil, dairy products from animals fed iodine-rich feed.
Dietary Reference Intake (DRI)*
150 micrograms
Deficiency Symptoms
Enlarged thyroid gland (goiter), sluggishness, and weight gain. Can cause severe retardation of developing fetus during pregnancy.
Iron
Primary Functions
Part of hemoglobin which carries oxygen to cells. Part of myoglobin which makes oxygen available for muscle contraction. Needed for use of energy by the cells.
Food Sources
Organ meats, red meat, fish, shellfish, poultry, enriched breads and cereals, egg yolks, legumes, leafy green vegetables, dried fruits, blackstrap molasses.
Dietary Reference Intake (DRI)*
8 milligrams
Deficiency Symptoms
Anemia, fatigue, muscle weakness, headaches, pale skin, inability to concentrate.
Magnesium
Primary Functions
Builds protein. Needed to release energy from food. Helps relax muscles after contraction. Helps resist tooth decay. Needed for transmission of nerve impulses.
Food Sources
Whole grains (especially wheat germ and bran), nuts, legumes, dark green vegetables, seafood, chocolate, cocoa.
Dietary Reference Intake (DRI)*
400 milligrams
Deficiency Symptoms
Confusion, nervousness, disorientation, hallucinations. Muscle weakness can progress to convulsions, and ultimately tetany. (Deficiencies are unlikely unless another medical problem exists.)
Phosphorus
Primary Functions
Aids in building strong bones and teeth. Activates vitamins for use. Needed to release energy from food. Needed for trans-mission of nerve impulses.
Food Sources
Milk and dairy products, fish, meat, poultry, egg yolks, nuts, legumes, peas, whole grains, processed foods, soft drinks.
Dietary Reference Intake (DRI)*
700 milligrams
Deficiency Symptoms
Muscle weakness, loss of appetite, bone pain. (Deficiencies are un-likely unless another medical problem exists.)
Potassium
Primary Functions
Needed for muscle contraction, heart action, nerve transmission, fluid balance. Involved in making proteins. Needed for maintenance of acid-base balance. Required for formation of glycogen (short-term storage of energy).
Food Sources
Lean meat, fresh fruits and vegetables, milk and dairy products, nuts, legumes, most salt substitutes.
Dietary Reference Intake (DRI)*
4,700 milligrams
Deficiency Symptoms
Muscle weakness, irregular heartbeat, apathy, confusion and loss of appetite. (Deficiencies are un-likely, unless excessive water loss occurs through vomiting, diarrhea, extreme sweating, or use of diuretics.)
Selenium
Primary Functions
Works with vitamin E to act as antioxidant and protect cell membranes.
Food Sources
Organ meats, seafood, lean meats, eggs, whole grains, wheat germ.
Dietary Reference Intake (DRI)*
55 micrograms
Deficiency Symptoms
Heart muscle abnormalities, anemia (rare).
Sodium
Primary Functions
Needed for normal fluid balance, both inside and outside cells; nerve transmission, acid-base balance, and muscle contraction.
Food Sources
Salt, soy sauce, monosodium glutamate (MSG), and most processed foods (especially regular soups, sauces, and cured meats), milk and dairy products.
Dietary Reference Intake (DRI)*
1,500 milligrams
Deficiency Symptoms
Muscle cramps, weakness, mental apathy, loss of appetite. (Deficiencies unlikely, unless another medical problem exists.)
Zinc
Primary Functions
Works as part of many enzymes. Present in insulin. Needed for making reproductive hormones, normal sense of taste, and wound healing.
Food Sources
Liver, egg yolks, oysters, lean meat, fish, poultry, milk and dairy products, whole grains, vegetables.
Dietary Reference Intake (DRI)*
11 milligrams
Deficiency Symptoms
Retarded growth, prolonged wound healing, slow sexual development, loss of taste (as a result, loss of appetite).
* Dietary Reference Intake (DRI) is a system of nutrition recommendations from the Institute of Medicine (IOM) of the National Academy of Sciences. The DRI system includes:
* Recommended Dietary Allowances (RDA) – Daily dietary intake levels of nutrients considered enough to meet the needs of 97-98% healthy individuals in each life stage and gender group
* Adequate Intakes (AIs) – Amounts of nutrients considered to be adequate where no RDAs have been established